Adaptive self-calibration for fast tuning phaselock loops

Claim 2

A self-calibrating radio tuner, comprising: a phase detector having first and second phase detector inputs and a phase detector output; an integrator having an integrator input coupled to the phase detector output and having an integrator output, said integrator receiving a phase output signal from the phase detector output and summing the phase output signal over time to provide on the integrator output an analog output signal representative of the phase output signal; a summer including first and second inputs, said first input coupled to the integrator output, said summer also having a summer output; an input-controlled oscillator ("ICO") having an input electrically connected to the summer output, said ICO also having an ICO output; a divider electrically interconnected between the ICO output and the first phase detector input; an analog-to-digital converter ("ADC") having an ADC input electrically connected to the integrator output and having an ADC output, said ADC receiving from the integrator output the analog output signal having an analog value and providing at the ADC output a digital signal representative of the analog value of the received analog output signal; a logic unit having a logic unit input interconnected to the ADC output and having a logic unit output; and a digital-to-analog converter ("DAC") having a DAC input electrically connected to the logic unit output and having a DAC output electrically connected to the summer's second input.

Claim 3

The radio tuner of claim 1, further comprising a down converter electrically connected to the ICO.

Claim 4

The radio tuner of claim 2, further comprising an antenna electrically connected to the down converter.

Claim 5

A self-calibrating radio tuner, comprising: a reference signal generator to generate a reference signal having a tune frequency; a phase detector connected to the reference signal generator to measure phase difference between the reference signal and a feedback signal received by the phase detector and to provide a representative output signal; an integrator coupled to the phase detector to sum the phase detector's output signal over time and provide a representative analog output signal on an integrator output; a summer coupled to the integrator output to sum the integrator's output with an analog steering signal received by the summer and provide a representative output signal; an input controlled oscillator ("ICO") electrically connected to the summer to provide an output signal with an actual tune frequency proportionate to the summer's output signal; a divider electrically interconnected between the ICO and the phase detector to selectably determine a desired tune frequency; an analog-to-digital converter ("ADC") coupled to the integrator output and having an ADC output, to receive the analog output signal having an analog value from the integrator output and provide at the ADC output a digital error signal representative of the analog value of the received analog output signal; a digital-to-analog converter ("DAC") having a DAC output coupled to the summer and also having a DAC input, the DAC providing at the DAC output the analog steering signal proportional to a digital input signal received at the DAC input; a memory containing electrical representations of steering signals associated with specific reference signals and temperatures; and a logic unit interconnected to the ADC output, the memory, and the DAC, programmed to perform method steps to select the analog steering signal, said method steps comprising the steps of: selecting an analog pre-steering signal by retrieving from the memory an analog steering signal referenced according to the desired tune frequency; providing the selected analog pre-steering signal to the DAC input for a selected time period; in response to the digital signal representative of the analog value of the received analog signal, selecting a corrected steering signal to minimize the error signal; and after operation of the radio tuner for a selected time period, providing the corrected steering signal to the DAC input.

Claim 6

A self-calibrating radio tuner, comprising: a reference signal generator to generate a reference signal having a tune frequency; a phase detector connected to the reference signal generator to measure phase difference between the reference signal and a feedback signal received by the phase detector and to provide a representative output signal; an integrator coupled to the phase detector to sum the phase detector's output signal over time and provide a representative analog output signal on an integrator output; a summer coupled to the integrator output to sum the integrator's output with an analog steering signal received by the summer and provide a representative output signal; an input controlled oscillator ("ICO") electrically connected to the summer to provide an output signal with an actual tune frequency proportionate to the summer's output signal; a divider electrically interconnected between the ICO and the phase detector to selectably determine a desired tune frequency; an analog-to-digital converter ("ADC") coupled to the integrator output and having an ADC output, to receive the analog output signal having an analog value from the integrator output and provide at the ADC output a digital error signal representative of the analog value of the received analog output signal; a digital-to-analog converter ("DAC") having a DAC output coupled to the summer and also having a DAC input, the DAC providing at the DAC output the analog steering signal proportional to a digital input signal received at the DAC input; a memory containing electrical representations of steering signals associated with specific reference signals and temperatures; and a logic unit interconnected to the ADC output, the memory, and the DAC, programmed to perform method steps to select the analog steering signal, said method steps comprising the steps of: selecting an analog pre-steering signal by retrieving from the memory an analog steering signal referenced according to the desired tune frequency; providing the selected analog pre-steering signal to the DAC input for a selected time period; in response to the digital signal representative of the analog value of the received analog signal, selecting a corrected steering signal to minimize the error signal; and after operation of the radio tuner for a selected time period, providing the corrected steering signal to the DAC input.

Claim 7

The radio tuner of claim 4, wherein the logic unit comprises a microprocessor.

Claim 8

The radio tuner of claim 5, wherein the logic unit further includes a memory.

Claim 9

The radio tuner of claim 4, wherein the logic unit comprises a programmable logic array.

Claim 10

The radio tuner of claim 4, wherein the logic unit comprises an emitter-coupled logic circuit.

Claim 11

The radio tuner of claim 4, wherein the logic unit includes an electrically programmable circuit.

Claim 12

The radio tuner of claim 4, wherein the logic unit is embodied in Gallium Arsenide circuitry.

Claim 13

The radio tuner of claim 4, further comprising a down converter electrically connected to the ICO.

Claim 14

The radio tuner of claim 11, further comprising an antenna electrically connected to the down converter.

Claim 17

The method of claim 13, wherein the step of generating a corrected steering signal further comprises the steps of storing the corrected steering signal.

Claim 18

The method of claim 13, wherein the steering signal comprises a digital signal, and the method further comprises the steps of converting the digital steering signal to an analog signal.

Claim 19

The method of claim 13, wherein the steering signal comprises an analog signal.

Claim 20

The method of claim 13, wherein the step of generating the steering signal comprises the steps of: generating a pre-steering signal in response to the division; after operation of the radio tuner for a selected time period, determining whether any change has occurred in the desired tune frequency; generating a corrected steering signal to minimize the error signal; and repeating the above-mentioned steps.

Claim 21

The method of claim 13, wherein the of step generating the steering signal comprises the steps of: generating a pre-steering signal in response to an initial temperature and initial reference signal; sensing the present temperature and reference signal; in response to a change in the temperature or the desired tune frequency, re-generating pre-steering signal in accordance with the sensed temperature and the desired tune frequency; and after operation of the radio tuner for a selected time period without any change in temperature or desired tone frequency, generating a corrected steering signal to minimize the error signal.